[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"detail-sidebar-cat-0-en-105":3,"doc-seo-661050-105":59,"doc-detail-661050-en":129},{"code":4,"msg":5,"data":6},0,"success",[7,13,18,23,28,33,38,43,48,51,55],{"id":8,"doc_module":4,"doc_module_name":9,"category_name":10,"show_sort_weight":11,"slug":12},1,"Document","Story & Novel",90,"story-novel",{"id":14,"doc_module":4,"doc_module_name":9,"category_name":15,"show_sort_weight":16,"slug":17},2,"Literature",80,"literature",{"id":19,"doc_module":4,"doc_module_name":9,"category_name":20,"show_sort_weight":21,"slug":22},4,"Exam",70,"exam",{"id":24,"doc_module":4,"doc_module_name":9,"category_name":25,"show_sort_weight":26,"slug":27},5,"Comic",60,"comic",{"id":29,"doc_module":4,"doc_module_name":9,"category_name":30,"show_sort_weight":31,"slug":32},6,"Technology",50,"technology",{"id":34,"doc_module":4,"doc_module_name":9,"category_name":35,"show_sort_weight":36,"slug":37},7,"Healthcare",40,"healthcare",{"id":39,"doc_module":4,"doc_module_name":9,"category_name":40,"show_sort_weight":41,"slug":42},8,"Research & Report",30,"research-report",{"id":44,"doc_module":4,"doc_module_name":9,"category_name":45,"show_sort_weight":46,"slug":47},9,"Religion & Spirituality",20,"religion-spirituality",{"id":46,"doc_module":4,"doc_module_name":9,"category_name":49,"show_sort_weight":46,"slug":50},"World Cup","world-cup",{"id":52,"doc_module":4,"doc_module_name":9,"category_name":53,"show_sort_weight":52,"slug":54},10,"Lifestyle","lifestyle",{"id":56,"doc_module":4,"doc_module_name":9,"category_name":57,"show_sort_weight":24,"slug":58},19,"General","general",{"code":4,"msg":60,"data":61},"ok",{"site_id":62,"language":63,"slug":64,"title":65,"keywords":66,"description":67,"schema_data":68,"social_meta":122,"head_meta":124,"extra_data":126,"updated_unix":128},105,"en","the-double-helix-structural-biology-overview","The Double Helix - Structural Biology Overview","","This document provides a comprehensive overview of the double helix structure of DNA, detailing the fundamental characteristics of its two polynucleotide strands. It explains key structural elements including the sugar-phosphate backbone, which consists of alternating deoxyribose and phosphate groups, and the antiparallel orientation of the strands, where one runs in a 5' to 3' direction while the other runs 3' to 5'. The text further elucidates the significance of base pairing, emphasizing how hydrogen bonds between purines and pyrimidines stabilize the helical configuration. Additionally, the document covers precise measurements such as the 3.4 angstrom spacing between base pairs, the 34 angstrom full turn length, and the 20 angstrom diameter of the helix. It also highlights the major and minor grooves formed by the backbones and contextualizes this discovery within scientific history, noting the seminal work of Francis Crick and James D. Watson in 1953, which uncovered the mechanism for genetic replication and inheritance, ultimately leading to their 1962 Nobel Prize. This educational summary serves as an essential reference for understanding the physical architecture of DNA molecules.",{"@graph":69,"@context":121},[70,84,104],{"@type":71,"itemListElement":72},"BreadcrumbList",[73,77,79,82],{"item":74,"name":75,"@type":76,"position":8},"https://docshare.wps.com","Home","ListItem",{"item":78,"name":9,"@type":76,"position":14},"https://docshare.wps.com/document/",{"item":80,"name":40,"@type":76,"position":81},"https://docshare.wps.com/document/research-report/",3,{"item":83,"name":65,"@type":76,"position":19},"https://docshare.wps.com/document/the-double-helix-structural-biology-overview/661050/",{"url":83,"name":65,"@type":85,"image":86,"author":91,"headline":65,"publisher":94,"fileFormat":97,"inLanguage":63,"description":67,"dateModified":98,"datePublished":98,"encodingFormat":97,"isAccessibleForFree":99,"interactionStatistic":100},"DigitalDocument",{"url":87,"@type":88,"width":89,"height":90},"https://docshare.wps.com/thumbnails/the-double-helix-structural-biology-overview/661050.png","ImageObject",300,407,{"name":92,"@type":93},"Margaret","Person",{"url":74,"name":95,"@type":96},"DocShare","Organization","application/pdf","2026-10-28",true,{"@type":101,"interactionType":102,"userInteractionCount":4},"InteractionCounter",{"@type":103},"ViewAction",{"@type":105,"mainEntity":106},"FAQPage",[107,113,117],{"name":108,"@type":109,"acceptedAnswer":110},"What is the significance of the antiparallel orientation in DNA?","Question",{"text":111,"@type":112},"The antiparallel orientation means the two strands run in opposite directions—one 5' to 3' and the other 3' to 5'—which is essential for the way DNA is assembled and read during biological processes.","Answer",{"name":114,"@type":109,"acceptedAnswer":115},"What discovery did Watson and Crick make in 1953?",{"text":116,"@type":112},"Francis Crick and James D. Watson worked out the double helix structure of DNA, which explained how DNA could be replicated and passed on from generation to generation.",{"name":118,"@type":109,"acceptedAnswer":119},"What are the primary structural dimensions of the DNA double helix?",{"text":120,"@type":112},"The double helix has a diameter of 20 angstroms, with 3.4 angstroms separating adjacent base pairs and a full turn occurring approximately every 34 angstroms.","https://schema.org",{"og:url":83,"og:type":123,"og:title":65,"og:site_name":95,"og:description":67},"article",{"robots":125,"canonical":83},"index,follow",{"doc_id":127,"site_id":62},661050,1793156746,{"code":4,"msg":5,"data":130},{"doc_id":127,"user_id":131,"nickname":92,"user_avatar":132,"doc_module":4,"category_id":39,"category_name":40,"doc_title":65,"doc_description":67,"doc_content":133,"file_id":134,"file_url":135,"file_type":136,"file_size":137,"view_count":4,"is_deleted":4,"is_public":8,"is_downloadable":8,"audit_status":8,"page_count":14,"language":138,"language_code":63,"site_id":62,"html_lang":63,"table_of_contents":139,"faqs":140,"seo_title":141,"seo_description":67,"update_tm":128,"read_time":24},137451207643,"https://ap-avatar.wpscdn.com/davatar_3d24733baf745e90a7e4bdd5f77d97b2","The Double Helix  \nThe double helix of DNA has these features:  \n• It contains two polynucleotide strands wound around each other.  \n• The backbone of each consists of  \nalternating deoxyribose and phosphate groups.  \n• The phosphate group bonded to the 5'carbon atom of one deoxyribose is covalently bonded to the 3' carbon of the next.  \n• The two strands are \"antiparallel\"; that is,  \none strand runs 5′ to 3′ while the other runs 3′ to 5′.  \n• The DNA strands are assembled in the 5′ to 3′ direction [ More] and, by convention, we\"read\" them the same way.  \n• The purine or pyrimidine attached to each deoxyribose projects in toward the axis of the helix.  \n• Each base forms hydrogen bonds with the one directly opposite it, forming base pairs (also called nucleotide pairs) .  \nDiscussion of base pairing in DNA  \n•  \n• 3.4 Å separate the planes in which adjacent base pairs are located.  \n• The double helix makes a complete turn in just over 10 nucleotide pairs, so each turn takes a little more (35 . 7 Å to be exact) than the 34 Å shown in the diagram.  \n• There is an average of 25 hydrogen bondswithin each complete turn of the double helix providing a stability of binding about as strong as what a covalent bond would provide.  \n• The diameter of the helix is 20 Å .  \n• The helix can be virtually any length; when fully stretched, some DNA molecules are as much as 5 cm (2 inches!) long.  \n• The path taken by the two backbones forms a major (wider) groove (from \"34 A\" to the top of the arrow) and a minor (narrower) groove (the one below) .  \nThis structure of DNA was worked out by Francis Crick and James D. Watson in 1953. It revealed how DNA—the molecule that Avery had shown was the physical substance of the genes—could be replicated and so passed on from generation to generation. For this epochal work, they shared a Nobel Prize in 1962.","cbCaiaIHxLRMhxm6","https://ap.wps.com/l/cbCaiaIHxLRMhxm6","pdf",285783,"English","# The Double Helix Structure\n## Features of the DNA Strand\n## Discussion of Base Pairing and Dimensions","[{\"question\":\"What is the significance of the antiparallel orientation in DNA?\",\"answer\":\"The antiparallel orientation means the two strands run in opposite directions—one 5' to 3' and the other 3' to 5'—which is essential for the way DNA is assembled and read during biological processes.\"},{\"question\":\"What discovery did Watson and Crick make in 1953?\",\"answer\":\"Francis Crick and James D. Watson worked out the double helix structure of DNA, which explained how DNA could be replicated and passed on from generation to generation.\"},{\"question\":\"What are the primary structural dimensions of the DNA double helix?\",\"answer\":\"The double helix has a diameter of 20 angstroms, with 3.4 angstroms separating adjacent base pairs and a full turn occurring approximately every 34 angstroms.\"}]","The Double Helix - Structural Biology Overview | PDF"]